The importance of psychology for shaping legal cannabis regulation

Different patterns of cannabis use can be traced directly back to different interactions between 2 types of variables: pharmacological and environmental. As legal cannabis expands in the U.S. and around the world, state and national regulatory agencies are gaining control over these variables. Specifically, regulatory agencies are increasingly capable of altering (a) the pharmacological properties of cannabis products and (b) the way these products are distributed to the population. Consequently, cannabis regulatory agencies are in a unique position to use evidence from psychological science to alter cannabis consumption patterns in ways that mitigate potential harm to public health. However, most state-level legal cannabis regulatory systems in the U.S. are not yet evidence-based or public health-oriented. This applied review and commentary draws on evidence from the psychological science literature to help regulators better understand the types of behaviors they must address and guide empirically supported regulation of THC-laden cannabis, whether used putatively for medical or recreational reasons. This review is organized into 3 parts that correspond to the 3 primary agents within the cannabis regulation ecosystem: (a) the cannabis consumer, (b) the cannabis industry, and (c) the cannabis regulatory agency. Within this structure, the review addresses critical psychological variables that drive cannabis consumer and industry behaviors and discusses how regulatory agencies can use this information to protect public health. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The Anticipated Effects of Cannabis Scale (AECS): Initial development and validation of an affect- and valence-based expectancy measure

Prior research suggests that cannabis expectancies are related to cannabis misuse and problems. Although there are established measures of cannabis expectancies, existing measures have psychometric limitations and/or are lengthy. Existing measures typically have a two-factor structure of positive and negative expectancies, but recent conceptualizations of alcohol expectancies support a valence- (positive vs. negative) and arousal-based (high vs. low arousal) structure. Thus, the present study sought to test a similar structure for cannabis. Cannabis expectancy items underwent 2 preliminary studies, assessing item valance/arousal (n = 233) and relevance to cannabis (n = 124). A final pool of 76 items underwent exploratory factor analysis (n = 303), and remaining items underwent confirmatory factor analysis in a separate sample (n = 469). Lastly, an additional sample (n = 435) examined validity. Results suggested a 3-factor structure (general positive, high arousal negative, low arousal negative) for the 17-item Anticipated Effects of Cannabis Scale (AECS), which was invariant across cannabis use frequency, sex, and race/ethnicity. Positive expectancies were strongly associated with cannabis use, whereas low arousal negative expectancies were protective against cannabis frequency; high arousal negative expectancies were strongly associated with more negative consequences and dependence symptoms. In addition, the proposed interpretation of AECS test scores showed evidence of incremental validity relative to another abbreviated measure. The current study provides initial support for the AECS, a brief, psychometrically sound cannabis expectancies measure. The AECS captures the full range of cannabis effects and may be suited to test discrepancies between cannabis expectancies and subjective response. Additional research is needed to validate its structure and predictive utility. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Intelligence quotient decline following frequent or dependent cannabis use in youth: a systematic review and meta-analysis of longitudinal studies

Previous systematic reviews and meta-analyses of cross-sectional data assessing the effect of cannabis on cognitive functioning and intelligence show inconsistent results. We hypothesized that frequent and dependent cannabis use in youth would be associated with Intelligence Quotient (IQ) decline. This study is a systematic review and meta-analysis. We searched Embase, PubMed and PsychInfo from inception to 24 January 2020. We included studies with non-treatment seeking samples and pre- and post-exposure measures of IQ. We requested data from authors if summary data was not available from published work. We preregistered our review with PROSPERO (ID no. CRD42019125624). We found seven cohort studies including 808 cases and 5308 controls. We found a significant effect for the association between frequent or dependent cannabis use in youth and IQ change, Cohen's d = -0.132 (95% CI -0.198 to -0.066) p < 0.001. Statistical heterogeneity between studies was also low at I2 = 0.2%. Study quality was moderate to high. This translates to an average decline of approximately 2 IQ points following exposure to cannabis in youth. Future studies should have longer periods of follow up to assess the magnitude of developmental impact.

Marijuana, but not alcohol, use frequency associated with greater loneliness, psychological distress, and less flourishing among young adults

OBJECTIVE

To assess whether frequency of marijuana and alcohol use are cross-sectionally associated with indicators of social and emotional well-being including loneliness, psychological distress, and flourishing across important life domains among young adults.

METHOD

The study sample included 562 participants ages 22-29 who were originally recruited from an urban Pacific Northwest region in the US as part of a longitudinal study of social role transitions and alcohol use. At one assessment, participants completed an online survey that included a 3-item measure of loneliness, a 4-item measure of depression and anxiety symptoms, and a 12-item measure of flourishing as well as measures of marijuana and alcohol use frequency. Linear and generalized linear models were used to estimate associations of marijuana and alcohol use frequency with indicators of well-being.

RESULTS

Greater frequency of marijuana use was associated with higher levels of loneliness, higher levels of psychological distress, and lower levels of flourishing, with the greatest difference observed for daily marijuana users compared to non-users. However, these indicators of well-being did not significantly differ by levels of alcohol use frequency.

CONCLUSION

Study findings suggest that frequent users of marijuana, but not alcohol, may experience more loneliness, more psychological distress, and less flourishing. Intervention approaches for frequent marijuana users may be warranted to reduce impacts of loneliness and psychological distress and improve overall well-being.

[Examination of emotion regulation difficulties, coping, impulsivity, external-internal control and sensation seeking among occasional and regular marijuana users]

INTRODUCTION

Several studies have investigated the relationship between personality and psychoactive substance use. Researches of personality and marijuana use suggests that certain personality traits differentiate between occasional and regular marijuana consumers. Understanding the relationship between individual persona - lity traits and marijuana use is a key step in the development of prevention and treatment methods. In the current study, we present the development of emotion regulation difficulties, coping with stress, impulsivity, external-internal control and sensation seeking in occasional and regular marijuana users.

METHODS

322 people participated in our study, within this 51 occasional and 56 regular marijuana users and 215 non-marijuana users who formed the control group. The examined personality traits were measured with the Diffi - culties in Emotion Regulation Scale, the Coping Inventory for Stressful Situations, the Barratt Impulsiveness Scale, the Internal-External Locus of Control Scale and the Sensation Seeking Scale.

RESULTS

Varying levels of marijuana use increased difficulty in emotion regulation as well as impulsivity. Addi tio nally, the use of emotion-oriented coping strategies were most common in occasional and regular marijuana use. Regular marijuana users were more likely to have external control than occasional users. Non-marijuana users were less sen - sation seekers that the two groups of marijuana users, however, we did not find significant difference between occasio nal and regular users.

Perceptions of U.S. and Canadian Cannabis Package Warnings Among U.S. Adults

BACKGROUND

Cannabis warning labels can communicate risks, but there is little research on warning perceptions and differences by product type.

METHODS

In a 2019 online survey, 1,000 U.S. adults (500 cannabis users and 500 cannabis non-users who used tobacco) were randomly assigned to view no warning or one of four U.S. or Canadian warnings displayed on images of packaging for dried flower or edible cannabis. The warnings described cannabis risks related to psychosis, addiction, lack of FDA oversight, and impaired driving. We used linear regression to examine perceptions of warnings and product harm as a function of product type (dried or edible) and warning. We examined which warning participants selected as most effective for discouraging youth use and impaired driving.

RESULTS

Participants found the addiction warning (cannabis users: B = -1.04, p < 0.001; cannabis non-users: B = 1.17, p < 0.001) and psychosis warning (users: B = -0.65, p < 0.05; non-users: B = -0.71, p < 0.05) less believable than the driving warning but indicated that they learned more from the psychosis warning than the driving warning (users: B = 0.88, p < 0.01; non-users (B = 1.60, p < 0.001). Participants viewing any warning considered smoking cannabis to be more harmful than those viewing no warning (all p < 0.05). The psychosis warning was most frequently selected as the best warning for discouraging youth use.

CONCLUSIONS

Warnings have the potential to educate consumers and impact cannabis harm perceptions. Warnings have similar effects across product types, potentially eliminating the need for product type-specific warnings. The association of cannabis use with risk for psychosis, a topic addressed in Canadian warnings, could be a useful topic of focus in U.S. warnings.

Parsing impulsivity in individuals with anxiety and depression who use Cannabis

BACKGROUND

Individuals with anxiety/depression may impulsively use cannabis to acutely induce positive affect and attenuate aversive mood states. However, few studies have attempted to parse impulsivity displayed by anxious/depressed cannabis users. This investigation examined what aspects of impulsivity characterize those individuals using self-report and functional MRI (fMRI) measures.

METHODS

Individuals with any lifetime anxiety/depression diagnoses and problematic cannabis use ("Anx/Dep+CB"; n=42) were compared to a propensity score-matched group with very low cannabis use ("Anx/Dep-lowCB"; n=42), and a healthy control group (n=37). Impulsivity was measured using the UPPS-P Impulsivity Questionnaire and the Stop Signal Task (SST) during fMRI. For UPPS-P, regression models estimated group-by-impulsivity subscale interactions with post-hoc pairwise tests. For the SST, similar regression models were estimated with four a-priori regions of interest (ROIs; right opercularis, orbitalis, dorsal and ventral anterior insula) during stop-success and stop-failure processing. Null SST findings were followed up using Bayes factor analysis to quantify the evidence in support of the null hypothesis.

RESULTS

For the UPPS-P, a significant group-by-subscale interaction indicated that the Anx/Dep+CB group exhibited higher levels of impulsivity on the negative- and positive-urgency subscales relative to both comparison groups. Higher negative-urgency correlated with heavier lifetime cannabis use across groups. For the SST, there were no ROI task activation differences. Bayes factor analysis determined the null findings were at least three times more likely than the alternative hypothesis for all ROIs.

CONCLUSIONS

Impulsivity under periods of heightened affect, but not motor response inhibitions, characterized anxious/depressed individuals who use cannabis.

BOLD responses to inhibition in cannabis-using adolescents and emerging adults after 2 weeks of monitored cannabis abstinence

RATIONALE

Previous studies have suggested that chronic cannabis use has been associated with increased blood oxygen level-dependent (BOLD) response during a response inhibition task; however, these studies primarily included males.

OBJECTIVES

We investigated whether gender moderated the effects of cannabis use on BOLD response and behavioral performance during a Go-NoGo task in adolescents and young adults following 2 weeks of monitored abstinence.

METHODS

Participants included 77 16-26-year olds (MJ = 36, controls = 41). An emotion-based Go-NoGo task required participants to inhibit their response during a calm face. A whole-brain analysis looked at differences between cannabis group, gender, and their interaction.

RESULTS

Significant greater BOLD responses were observed in cannabis users compared with that in controls in the left frontal cortex, left cingulate cortex, and the left thalamus during correct response inhibitions; gender did not moderate these effects.

CONCLUSION

Supporting previous research, cannabis users showed greater BOLD responses in core areas associated with response inhibition during a Go-NoGo task, even after a minimum of 2 weeks of abstinence.

Longitudinal associations between amygdala reactivity and cannabis use in a large sample of adolescents

RATIONALE

The amygdala is a key brain structure to study in relation to cannabis use as reflected by its high-density of cannabinoid receptors and functional reactivity to processes relevant to drug use. Previously, we identified a correlation between cannabis use in early adolescence and amygdala hyper-reactivity to angry faces (Spechler et al. 2015).

OBJECTIVES

Here, we leveraged the longitudinal aspect of the same dataset (the IMAGEN study) to determine (1) if amygdala hyper-reactivity predicts future cannabis use and (2) if amygdala reactivity is affected by prolonged cannabis exposure during adolescence.

METHODS

First, linear regressions predicted the level of cannabis use by age 19 using amygdala reactivity to angry faces measured at age 14 prior to cannabis exposure in a sample of 1119 participants. Next, we evaluated the time course of amygdala functional development from age 14 to 19 for angry face processing and how it might be associated with protracted cannabis use throughout this developmental window. We compared the sample from Spechler et al. 2015, the majority of whom escalated their use over the 5-year interval, to a matched sample of non-users.

RESULTS

Right amygdala reactivity to angry faces significantly predicted cannabis use 5 years later in a dose-response fashion. Cannabis-naïve adolescents demonstrated the lowest levels of amygdala reactivity. No such predictive relationship was identified for alcohol or cigarette use. Next, follow-up analyses indicated a significant group-by-time interaction for the right amygdala.

CONCLUSIONS

(1) Right amygdala hyper-reactivity is predictive of future cannabis use, and (2) protracted cannabis exposure during adolescence may alter the rate of neurotypical functional development.

Impact of 2 Weeks of Monitored Abstinence on Cognition in Adolescent and Young Adult Cannabis Users

OBJECTIVES

Previous research suggests recovery from cannabis-related deficits in verbal learning and memory functioning after periods of cannabis abstinence in adolescents. Here, we examine how cannabis cessation affects cognitive performance over 2 weeks of monitored abstinence compared to controls in adolescents and young adults.

METHODS

Seventy-four participants (35 cannabis users) aged 16-26 ceased all cannabis, alcohol, and other illicit substance consumption for a 2-week period; abstinence was monitored via weekly urinalysis, breath, and sweat patch testing. Starting at baseline, participants completed weekly abbreviated neuropsychological batteries. Measures included tests of attention, inhibition, verbal working memory, and learning. Repeated measures assessed within and between subject effects for time and group status, while controlling for past year alcohol and nicotine use.

RESULTS

Cannabis users showed increased performance compared to controls on sustained attention tasks after 2 weeks of cannabis use.

CONCLUSIONS

Deficits in attention, but not verbal learning and memory, recovered after 2 weeks of monitored abstinence. This differs from previous literature, suggesting that other cognitive domains may show signs of recovery after periods of cannabis cessation in adolescents and young adults.

Initial evaluation of Manitoba's cannabis surveillance system

The Government of Manitoba created a cannabis public health surveillance system in 2018 in preparation for nonmedical cannabis legalization on 17 October, 2018. An initial evaluation was conducted to assess the usefulness, flexibility and simplicity attributes of the system, using an online stakeholder survey, website metrics, system analysis and interviews. Resulting recommendations included creating a detailed communication plan for surveillance products, changing the format and frequency of reporting, maintaining strong relationships with partners and building towards a centralized provincial substance use surveillance database and surveillance system.

Incidental finding of age and time disorientation in a clinical sample of patients with schizophrenia: Findings from a short term follow up survey regarding cannabis use

Age disorientation has been described in a subtype of patients with schizophrenia. The current article reports on an incidental finding from our survey study on patterns of cannabis use pre-post legalization in patients with schizophrenia. For the purpose of the survey study, patients were asked to fill out a total of 41 survey questions. The same participants were contacted over the phone 8 weeks post-legalization. Responses to the survey questions were consistent pre- and post-legalization except for four items which required estimation of time/age. This incidental finding highlights the need for further exploration of this phenomenon by future studies.

Marijuana use and health behaviors in a US clinic sample of patients with sickle cell disease

Introduction

As marijuana use becomes more common, it is essential clinicians understand the relationship between marijuana use and health behaviors.

Methods

Using a retrospective cohort of adolescents and adults with sickle cell disease (SCD) stratified into a young (<25 years) and older cohort (> = 25 years), we conducted multiple linear regression examining relationship of marijuana use (independent variable) on each dependent variable (SCD self-management score and pain management).

Results

Among young cohort, 16.9% used marijuana compared to 21.8% of older cohort. The younger cohort reporting marijuana use had lower mean self-care scores (β = -2.74;p = 0.009) and were more likely to have admissions to the hospital for pain (β = 0.87;p = 0.047) compared to non-users. In contrast, the older cohort reporting marijuana use had more days treating pain at home (β = 0.44;p = 0.035).

Conclusions

Only a minority of patients with SCD reported lifetime marijuana use. Among those reporting marijuana use, there were different associations with self-care and health-related behaviors by age. The older cohort who endorsed marijuana use reported more days of treating pain at home, although this did not translate into increased acute care visits for pain crisis. Among youth, endorsing marijuana use was associated with worse SCD self-care.

Youth's Proximity to Marijuana Retailers and Advertisements: Factors Associated with Washington State Adolescents' Intentions to Use Marijuana

The current study explored the influences of advertising exposure, numbers of marijuana retailers, distance to retailers, and constructs from the integrative model of behavioral prediction, including outcome beliefs, perceived norms, and efficacy, on youth's intentions to use marijuana in a state in which the use of recreational marijuana is legal. A state-wide online cross-sectional survey of 350 adolescents ages 13-17, residing in Washington state, was conducted in June 2018. The results of the regression analysis suggest that exposure to marijuana advertising, positive and negative outcome beliefs, and perceived peer norms were associated with intention to use marijuana. Distances to retailers moderated the relationships between exposure to advertising and intentions, as well as between positive outcome beliefs and intentions. States that have legalized recreational marijuana should continue considering the location of retailers in relation to neighborhoods and advertising regulations to reduce the appeal to youth. Additionally, prevention efforts could aim to influence outcome beliefs and norms in an attempt to reduce adolescents' intentions to use recreational marijuana.

Digital media use and subsequent cannabis and tobacco product use initiation among adolescents

BACKGROUND

Digital media engagement, such as browsing the internet or social media posting, may be associated with cannabis and tobacco product use initiation among adolescents. Whether certain digital media exposure confers greater - or reduced - risk for specific cannabis or tobacco products is unknown.

METHODS

Adolescents completed surveys on digital media and substance use every 6 months from 2015 to 2017 (4 waves). Self-reported digital media use (14 items) was classified into six subcategories (e.g., "social media posting," "reading news/articles & browsing photos"). Random-effect repeated-measures regression models examined the association of exposure to each digital media subcategory with subsequent cannabis or tobacco product use initiation in the next 6 months, among baseline cannabis and tobacco never-users (n = 1841; n = 1558, respectively).

RESULTS

High frequency digital media use (multiple times/day) of "social media posting" (vs. no high frequency use; OR = 1.95; 95%CI:1.20-3.17) and "checking in" (OR = 1.71; 95%CI:1.23-2.38) was associated with greater odds of any cannabis product use initiation 6 months later. "Reading news/articles & browsing photos" was associated with decreased odds of initiation (OR = 0.52; 95%CI:0.34-0.79). "Checking in" and "reading news/articles & browsing photos" were similarly associated with any tobacco use initiation. "Chatting and shopping" was associated with greater odds (OR = 4.63; 95%CI:1.53-14.06) of e-cigarette initiation, but not of other product use initiation.

CONCLUSIONS

Some subcategories of digital media use conferred increased odds, others conferred reduced odds, and others were not associated with cannabis and tobacco use initiation. Research exploring mechanisms that put users of specific digital media at greater risk for substance use initiation is warranted.

On the discounting of cannabis and money: Sensitivity to magnitude vs. delay

BACKGROUND

While using most drugs of abuse is associated with higher than control rates of delay discounting, cannabis use may be the exception. As such, between-commodity differences in delay discounting (i.e., money vs. cannabis) have not been thoroughly examined. We examined these between-commodity differences using modern analytic techniques to disentangle effects of subjects' sensitivity to magnitude and delay as potential drivers of any obtained delay discounting rate differences.

METHOD

; Fifty-eight college students (n = 33 cannabis users, n = 25 non-users) completed a monetary delay discounting task - with the cannabis users completing the cannabis problems questionnaire as well a delay discounting of cannabis task- in an on-campus laboratory.

RESULTS

Responding between groups differed on the cannabis problems questionnaire, but not on delay discounting of monetary outcomes. Cannabis users, however, discounted cannabis at higher rates than money. Multilevel logistic regression revealed that these between-commodity delay discounting differences were due to subjects' differential sensitivity to the magnitude of these two commodities, rather than sensitivity to delay to receiving these commodities.

CONCLUSIONS

Although differences in delay discounting rate were not obtained between students that did and did not use cannabis, cannabis users did discount cannabis at higher rates than they did money - suggesting considerable generality of the between commodity differences in delay discounting obtained elsewhere. The current between-commodity delay discounting differences appear to be driven by differential sensitivity to the reinforcer magnitudes presented in each task - a finding that awaits replication across other comparisons before statements about generality can be made.

Blunted highs: Pharmacodynamic and behavioral models of cannabis tolerance

Acute exposure to cannabis comes with neurocognitive impairment, leading to increased risk of human error and injury. Evidence however indicates that such acute effects are less prominent in chronic users, suggesting cannabis tolerance. Models of cannabis tolerance stress the importance of neurobiological or behavioral adaptations following repeated cannabis exposure. The pharmacodynamic model relates neuroadaptive changes in the brain to a blunted response to cannabis. Downregulation of CB1 receptors in chronic cannabis users has been associated with a normalization of dopaminergic output from the ventral tegmental area to the mesolimbic circuit, and a reduction of impairment during acute cannabis exposure. Such neuroadaptions are absent in occasional users, who show strong increments of dopamine and glutamate levels in the striatum, a loss of functional connectivity within the mesolimbic circuit and neurocognitive impairments when exposed to cannabis. Evidence for a behavioral model of cannabis tolerance that poses that users can have volitional control to overcome functional impairment during cannabis intoxication is relatively weak, and at best shows limited control over a limited number of behavioral functions. Cannabis tolerance is most likely to occur in users that consume high doses of cannabis continuously, at a high pace, for a prolonged period of time. Knowledge on frequency, dose and duration of cannabis use that is needed to achieve, maintain or lessen tolerance however is very limited, but will be of importance in the context of cannabis therapeutics and in legal settings when evaluating the impact of cannabis exposure on human function.

Information Seeking as A Predictor of Risk Behavior: Testing A Behavior and Risk Information Engagement Model (BRIE)

Prior theoretical models of information seeking have examined its role, primarily, as a determinant of recommended behaviors. In this study, we develop and test the "behavior and risk information engagement" (BRIE) model, which accounts for the reciprocal effects of information seeking from interpersonal and media sources on two risk behaviors - nonmedical marijuana and amphetamine use. We test the model among young Israeli adults (N = 800) using a three-wave prospective observational study (at 6-month intervals). Autoregressive cross-lagged structural equation models showed good fit. Information seeking from interpersonal sources at baseline predicted amphetamine use and marijuana use at 6 months. In both models, seeking drug-related information from interpersonal sources at baseline was also a predictor of seeking information from media sources at 6 months. Information seeking from media sources at 6 months was also a significant predictor of amphetamine use at 12 months. Implications for theory and practice are discussed.

Pharmacodynamic effects of vaporized and oral cannabidiol (CBD) and vaporized CBD-dominant cannabis in infrequent cannabis users

INTRODUCTION

The use and availability of oral and inhalable products containing cannabidiol (CBD) as the principal constituent has increased with expanded cannabis/hemp legalization. However, few controlled clinical laboratory studies have evaluated the pharmacodynamic effects of oral or vaporized CBD or CBD-dominant cannabis.

METHODS

Eighteen healthy adults (9 men; 9 women) completed four, double-blind, double-dummy, drug administration sessions. Sessions were separated by ≥1 week and included self-administration of 100 mg oral CBD, 100 mg vaporized CBD, vaporized CBD-dominant cannabis (100 mg CBD; 3.7 mg THC), and placebo. Study outcomes included: subjective drug effects, vital signs, cognitive/psychomotor performance, and whole blood THC and CBD concentrations.

RESULTS

Vaporized CBD and CBD-dominant cannabis increased ratings on several subjective items (e.g., Like Drug Effect) relative to placebo. Subjective effects did not differ between oral CBD and placebo and were generally higher for CBD-dominant cannabis compared to vaporized CBD. CBD did not increase ratings for several items typically associated with acute cannabis/THC exposure (e.g., Paranoid). Women reported qualitatively higher ratings for Pleasant Drug Effect than men after vaporized CBD and CBD-dominant cannabis use. CBD-dominant cannabis increased heart rate compared to placebo. Cognitive/psychomotor impairment was not observed in any drug condition.

CONCLUSIONS

Vaporized CBD and CBD-dominant cannabis produced discriminable subjective drug effects, which were sometimes stronger in women, but did not produce cognitive/psychomotor impairment. Subjective effects of oral CBD did not differ from placebo. Future research should further elucidate the subjective effects of various types of CBD products (e.g., inhaled, oral, topical), which appear to be distinct from THC-dominant products.

Characterizing motivations for cannabis use in a cohort of people who use illicit drugs: A latent class analysis

Background

Cannabis use is common among marginalized people who use illicit drugs (PWUD) but reasons for use remain poorly investigated. We sought to explore how different intentions for cannabis use relate to social, structural, and behavioural factors among PWUD in Vancouver, Canada.

Methods

We used data from cannabis-using participants in two community-recruited prospective cohort studies of PWUD. Using latent class analysis, we identified discrete cannabis-using groups based on self-reported intentions for use. Generalized estimating equations were used to examine correlates of class membership.

Results

Between June 2016 and December 2018, 2,686 observations from 897 participants cannabis-using PWUD were analyzed. Four latent classes of cannabis use emerged: Class 1 (31.6%), characterized by non-medical purposes; Class 2 (37.5%), characterized by non-pain therapeutic use (e.g., stress, nausea/loss of appetite, and insomnia); characterized by Class 3 (21.9%) predominantly pain relief; and Class 4 (9.0%), characterized by a wide range of therapeutic uses in addition to pain management, including insomnia, stress, nausea/loss of appetite, and harm reduction. Class-specific structural, substance-, and health-related differences were observed, including indicators of better physical and mental health among the “recreational” class, despite evidence of more structural vulnerabilities (e.g., homelessness, incarceration).

Conclusions

Our findings demonstrate a wide spectrum of motivations for cannabis use among PWUD. We observed important health-related differences between latent classes, demonstrating possible unmet healthcare needs among PWUD reporting therapeutic cannabis use. These findings inform ongoing policy surrounding access to cannabis for harm reduction purposes and applications of medical cannabis for PWUD.

Does Cannabis Use Predict More Severe Types of Alcohol Consequences? Longitudinal Associations in a 3-Year Study of College Students

BACKGROUND

Prior research shows that negative drinking outcomes among young adults may be exacerbated by cannabis use. However, to date, there have been few longitudinal studies of associations between cannabis use and negative alcohol-related consequences. This study examined longitudinal within-person associations between cannabis use and several domains of negative alcohol consequences among young adults and explored the moderating role of sex.

METHOD

We analyzed data from N = 997 students assessed 4 times per year over the first 3 years of university. At each time point, participants completed measures of past-month cannabis use frequency, typical weekly number of drinks, and 8 domains of negative alcohol consequences. Longitudinal associations were examined in multilevel models.

RESULTS

Within-person changes in frequency of cannabis use were not uniquely associated with changes in total alcohol consequences aggregated across several alcohol consequence domains. However, when examining alcohol consequence domains separately, within-person increases in cannabis use frequency were specifically associated with increases in some (but not all) of the more severe types of alcohol consequences, including risky behaviors, poor self-care, and alcohol dependence symptoms. No support was observed for the moderating role of sex in the longitudinal within-person associations between cannabis use and alcohol consequence domains.

CONCLUSIONS

Findings suggest that within-person changes in cannabis use frequency among young adults are associated with corresponding changes in some domains of alcohol consequences (but not others) when examined over the course of several years. Results may inform targeted harm reduction interventions for young adult drinkers who use cannabis, although future research is needed to clarify the mechanisms of the observed associations.

Examining interactions within the theory of planned behavior in the prediction of intentions to engage in cannabis-related driving behaviors

Objective: As marijuana use becomes more available to college students through increasing legal reform, this paper seeks to examine intentions for driving under the influence of cannabis (DUIC) and riding with a high driver (RWHD) through the lens of the theory of planned behavior (TPB) and assess potential interactions between personal attitudes, subjective norms, perceived behavioral control (PBC), and sex. Participants: Undergraduate college students (N = 311) completed online surveys in September, 2013. Method: Participants self-reported their attitudes toward DUIC, subjective norms, PBC, past DUIC and RWHD, and intentions to DUIC and RWHD. Results: Participants' attitudes toward DUIC, subjective norms, and PBC were strongly associated with intentions to DUIC and RWHD bivariately. In regression models, attitudes and PBC were both positively and significantly related to intentions to DUIC and RWHD. Conclusions: DUIC and RWHD are concerns for college populations. Targeting personal attitudes and perceived behavioral control via interventions may reduce these behaviors.

The role of perceived discrimination in substance use trajectories in Hispanic young adults: A longitudinal cohort study from high school through emerging adulthood

PURPOSE

Associations between discrimination and substance use have been identified cross-sectionally in multiple populations including Hispanics. However, there is limited research exploring this phenomenon longitudinally in Hispanic youth over the transition from adolescence through emerging adulthood (EA).

METHODS

Hispanic youth in Southern California (n = 1457) completed surveys over 11 years, from 2006 to 2017, including three high school collection waves and five EA collection waves. Multinomial logistic regression models were used to explore the associations between perceived discrimination during high school and cigarette and marijuana use in both high school and EA, controlling for gender, socioeconomic status, acculturation, and EA discrimination.

RESULTS

Compared with those who never used cigarettes or marijuana in high school and EA, perceived discrimination in high school was a significant predictor of two patterns of use: high school initiators who discontinued use of smoking (RRR = 1.677, 95%CI = 1.292-2.176) and/or marijuana (RRR = 1.464, 95%CI = 1.162-1.844), and high school initiators who continued smoking (RRR = 1.492, 95%CI = 1.196-1.861) and/or marijuana use (RRR = 1.249, 95%CI = 1.052-1.482) into EA. For late initiators who did not use in high school but started in EA, perceived high school discrimination was a significant predictor for cigarette smoking (RRR = 1.193, 95%CI = 1.036-1.373) but not for marijuana use.

CONCLUSIONS

Perceived discrimination during adolescence is associated with substance use trajectories across both adolescence and EA. Culturally tailored prevention programs that provide training in skills to cope with psychosocial stressors could improve Hispanic adolescent health.

Simultaneous Alcohol and Marijuana Use: A Brief Measure of Motives

OBJECTIVE

Increasing numbers of substance users report simultaneous alcohol and marijuana (SAM) use such that their effects overlap. More research is needed to understand what motivates this behavior, especially to inform interventions that address SAM use. A 26-item measure of SAM motives was designed and tested in previous research. The purpose of the current study was to validate that measure and create a briefer version of it.

METHOD

Using two waves of data from a multi-site sample of college students (n = 1,014), exploratory and confirmatory factor analyses were conducted to develop a brief 11-item SAM Motives Measure (B-SMM). Negative binomial regression analyses were conducted to assess the reliability and validity of both the original and brief measures.

RESULTS

The brief measure contains four subscales (conformity, positive effects, calm/coping, and social) that match the empirically supported motivational model of substance use. Internal consistency of the subscales ranged from .77 to .87. Most subscales significantly predicted frequency and consequences of SAM use both concurrently and prospectively.

CONCLUSIONS

The psychometrically sound measure developed in this study facilitates the examination of SAM motives in clinical settings with time-constrained patient contact and can be valuable for research involving frequent and repeated measures of substance use behaviors.

Motives Matter: Cannabis use motives moderate the associations between stress and negative affect

Young adults in the U.S. report high levels of stress which are known to contribute to depression and anxiety. Regular cannabis users frequently cite coping with stress as their primary motivation for use. However, research indicates that coping motives are associated with potentially negative outcomes, including cannabis-related problems and negative affect. Therefore, the theoretical rationale for the present study is that using cannabis to cope with stress may be maladaptive as it may exacerbate the same problems users are trying to ameliorate. That is, using cannabis to cope may potentiate links between stress and negative affect. We therefore sought to investigate whether cannabis use motives moderate the associations between stress and negative affect. A sample of 988 cannabis using college students completed an anonymous online survey containing measures of cannabis use, cannabis use motives, stress, depression, and anxiety. Correlation analyses revealed significant positive relationships between these variables. Moderation analyses indicated that coping motives was a significant moderator of the relationship between stress and depression, controlling for anxiety. In contrast, expansion and conformity motives were significant moderators of the relationship between stress and anxiety, controlling for depression. While cannabis may provide temporary relief from symptoms of stress, depression, and anxiety, using cannabis to cope may be related to higher levels of depression, and use of cannabis for expansion and conformity may be related to higher levels of anxiety. These findings have practical implications and contribute to emerging evidence demonstrating that motives for cannabis use may predict differential mental health outcomes.